A folding mechanism and a folding machine having the same

Abstract

The present application discloses a folding mechanism, which relates to the field of pipe processing equipment. The folding mechanism is used to bend the pipe mouth edge of the pipe fitting, and includes: a folding mold, one end of which has a notch, and the pipe mouth edge to be bent of the pipe fitting is inserted into the notch; a rotating mechanism, which drives the folding mold and / or the pipe fitting to rotate around the pipe mouth edge to be bent, so that the folding mold forms an angle with respect to the pipe fitting, and the angle is less than 180°. The embodiment of the present application clamps the pipe mouth edge to be bent of the pipe fitting through the notch of the folding mold, and then drives the folding mold and / or the pipe fitting to rotate around the pipe mouth edge to be bent, so that the folding mold forms an angle with respect to the pipe fitting, thereby achieving folding. The technical solution of the embodiment of the present application solves the problem that the mold in the pipe folding mechanism of the prior art is easy to break and has large loss, improves the efficiency of folding the pipe fitting, and enables the pipe fitting to meet the requirements of subsequent welding.

Description

Technical Field

[0001] The present application relates to the field of pipe processing equipment, and in particular to a folding mechanism and a folding machine having the folding mechanism. Background Art

[0002] In the prior art, when processing pipe fittings that need to be welded, a milling cutter or grinder is usually used to mill or grind the port edge of the pipe fitting that needs to be welded to meet the welding quality requirements; when the wall of the workpiece is thin, this will reduce the strength of the weld, directly affecting the strength of the entire structure and seriously affecting the stability of the product.

[0003] In order to solve the above problems, the Chinese utility model patent with announcement number CN205110476U discloses a bending mechanism for bending the edge of a metal pipe and a device for installing the mechanism, including a forming die for inserting the metal pipe, a recess is provided on the shoulder of the forming die; a punch mechanism for folding the metal pipe, the punch mechanism includes a punch, and the working end of the punch is provided with a convex head adapted to the recess of the forming die.

[0004] In the above technical solution, the notch on the forming die and the convex head on the punch can form a folded edge at the end of the pipe fitting to facilitate subsequent welding. However, the forming die is easily broken by the strong impact of the punch, resulting in a high downtime rate, high maintenance costs, and low production capacity, which needs to be improved urgently. Summary of the invention

[0005] The purpose of the present application is to provide a folding mechanism to solve the problem of easy breakage and large loss of the mold in the pipe folding mechanism in the prior art, to improve the efficiency of the pipe folding, and to enable the pipe to meet the requirements of subsequent welding.

[0006] To achieve the above-mentioned purpose, the embodiment of the present application adopts the following technical scheme: a folding mechanism, which is used to bend the edge of the tube mouth to be bent of the pipe fitting, and the edge of the tube mouth to be bent is a straight edge, including: a folding mold, one end of which has a notch, and the edge of the tube mouth to be bent of the pipe fitting is inserted into the notch; a rotating mechanism, which drives the folding mold and / or the pipe fitting to rotate around the edge of the tube mouth to be bent, so that the folding mold forms an angle with respect to the pipe fitting, and the angle is less than 180°.

[0007] In the above technical scheme, the embodiment of the present application clamps the edge of the pipe to be bent by the notch of the folding die, and then drives the folding die and / or the pipe to rotate around the edge of the pipe to be bent, so that the folding die forms an angle with respect to the pipe, thereby achieving folding. The technical scheme of the embodiment of the present application solves the problem that the mold in the pipe folding mechanism in the prior art is easy to break and has a large loss, improves the efficiency of the pipe folding, and enables the pipe to meet the requirements of subsequent welding.

[0008] Further, according to an embodiment of the present application, the folding mold includes an upper mold and a lower mold, the lower mold is connected to the upper mold, and a notch is set at the connection between the lower mold and the upper mold.

[0009] Further, according to an embodiment of the present application, the upper mold has a first width, and the first width is not greater than the inner diameter of the pipe mouth of the pipe fitting.

[0010] Further, according to an embodiment of the present application, the upper mold has a first width, the lower mold has a second width, and the first width is equal to the second width.

[0011] Further, according to an embodiment of the present application, the upper mold has a first width, the lower mold has a second width, and the first width is greater than the second width.

[0012] Further, according to an embodiment of the present application, the upper mold has a first width, the lower mold has a second width, and the first width is smaller than the second width.

[0013] Further, according to an embodiment of the present application, the lower mold has a second width, which is greater than the outer diameter of the pipe fitting and covers the outer side of the edge of the pipe mouth to be bent.

[0014] Further, according to an embodiment of the present application, the rotating mechanism includes a power mechanism.

[0015] Further, according to an embodiment of the present application, the power mechanism drives one end of the folding mold to lift upward.

[0016] Further, according to an embodiment of the present application, the power mechanism drives the end of the pipe that does not need to be bent to lift up.

[0017] Further, according to an embodiment of the present application, the power mechanism drives one end of the folding mold and the end of the pipe that does not need to be bent to lift up respectively.

[0018] Further, according to an embodiment of the present application, the rotating mechanism includes a rotating table, the rotating table has a rotating axis, and the rotating axis is aligned with the pipe mouth to be bent.

[0019] Further, according to an embodiment of the present application, the folding mold is installed on a rotating table.

[0020] Further, according to an embodiment of the present application, the pipe is installed on a rotating table.

[0021] Further, according to an embodiment of the present application, there are two rotating tables, and the two rotating tables are respectively installed with folding molds and pipe fittings.

[0022] Further, according to an embodiment of the present application, the folding mechanism also includes a pressing mechanism.

[0023] Further, according to an embodiment of the present application, the pressing mechanism is arranged above the pipe.

[0024] Further, according to an embodiment of the present application, the pressing mechanism is arranged above the folding mold.

[0025] Further, according to an embodiment of the present application, the folding mechanism also includes a demoulding mechanism, and the demoulding mechanism is connected to the folding mold.

[0026] In order to achieve the above-mentioned purpose, an embodiment of the present application also discloses a folding machine having a folding mechanism as described above.

[0027] In order to achieve the above object, the embodiment of the present application further discloses a folding method, comprising the following steps:

[0028] Insertion: insert the edge of the pipe to be bent into the groove of the folding die;

[0029] Folding drives the folding die and / or the pipe fitting to rotate around the edge of the pipe to be bent, so that the folding die forms an angle with respect to the pipe fitting, and the angle is less than 180°.

[0030] Further, according to an embodiment of the present application, in the insertion step, the folding mold clamps the inner wall of the edge of the pipe mouth to be bent.

[0031] Further, according to an embodiment of the present application, in the folding step, one end of the folding mold is driven to lift upward to achieve folding.

[0032] Further, according to an embodiment of the present application, in the folding step, the end of the pipe that does not need to be bent is lifted upward to achieve folding.

[0033] Further, according to an embodiment of the present application, in the hemming step, one end of the hemming mold and the end of the pipe that does not need to be bent are lifted upward to achieve hemming.

[0034] Further, according to an embodiment of the present application, one end of the folding mold and the end of the pipe that does not need to be bent are lifted upward to achieve folding.

[0035] Further, according to an embodiment of the present application, the hemming mold or the metal tube is pressed before the hemming step.

[0036] Further, according to an embodiment of the present application, after the hemming step, the hemming mold is pulled out of the tube.

[0037] Further, according to an embodiment of the present application, after the flanging step, the tube is separated from the flanging mold by lifting the flanging mold upward.

[0038] In order to achieve the above-mentioned purpose, an embodiment of the present application further discloses a pipe fitting having a folded edge, which is a straight edge and is formed by bending by the folding mechanism as described above or by the folding method as described above.

[0039] Further, according to an embodiment of the present application, the pipe fitting is a triangular pipe, a rectangular pipe, a polygonal pipe, a semicircular pipe or a special-shaped pipe.

[0040] In order to achieve the above-mentioned purpose, an embodiment of the present application further discloses an object having a pipe fitting as described above.

[0041] Compared with the prior art, the present application has the following beneficial effects: the present application clamps the edge of the pipe to be bent by the notch of the folding die, and then drives the folding die and / or the pipe to rotate around the edge of the pipe to be bent, so that the folding die forms an angle with respect to the pipe, thereby achieving folding. The technical solution of the embodiment of the present application solves the problem that the mold in the folding mechanism of the pipe in the prior art is easy to break and has a large loss, improves the efficiency of folding the pipe, and enables the pipe to meet the requirements of subsequent welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0043] Figure 1 It is a structural schematic diagram of a folding mechanism in an embodiment of the present application.

[0044] Figure 2 yes Figure 1 A partial enlarged view of the middle folding mold.

[0045] Figure 3 yes Figure 1 Schematic diagram of the insertion structure of the middle tube fitting and the folding die.

[0046] Figure 4 It is a structural schematic diagram of a folding mechanism in another embodiment of the present application.

[0047] Figure 5 yes Figure 4 A side view of the folding mechanism.

[0048] Figure 6 yes Figure 4 Schematic diagram of the folding mold structure.

[0049] In the attached figure

[0050] 1. Folding die 11, notch 12, upper die

[0051] 13. Lower mold 2, pipe fitting 3, rotating table

[0052] 4. Power mechanism 5. Pressing mechanism 6. Demolding mechanism DETAILED DESCRIPTION

[0053] In order to make the purpose and technical solution of the present invention clearly and completely described, and the advantages more clearly understood, the embodiments of the present invention are further described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are part of the embodiments of the present invention, rather than all of the embodiments, and are only used to explain the embodiments of the present invention, and are not used to limit the embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] In the description of the present invention, it should be noted that the terms "center", "middle", "upper", "lower", "left", "right", "inner", "outer", "top", "bottom", "side", "vertical", "horizontal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "one", "first", "second", "third", "fourth", "fifth", "sixth" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0055] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] For the purpose of simplicity and illustration, the principles of the embodiments are mainly described by reference to examples. In the following description, many specific details are proposed to provide a thorough understanding of the embodiments. However, it is obvious that for those of ordinary skill in the art, these embodiments may not be limited to these specific details in practice. In some instances, known methods and structures are not described in detail to avoid making these embodiments unnecessarily difficult to understand. In addition, all embodiments can be used in combination with each other.

[0057] The present application discloses a folding mechanism, which is used to bend the edge of a pipe to be bent, and the edge of the pipe to be bent is a straight edge. The folding mechanism includes a folding die and a rotating mechanism. One end of the folding die has a notch, and the edge of the pipe to be bent of the pipe can be inserted into the notch, and the notch can press the inner side of the edge of the pipe to be bent. The rotating mechanism is used to drive the folding die and / or the pipe to rotate around the pipe edge, so that the folding die forms an angle with respect to the pipe, and the angle is less than 180°.

[0058] In the above technical solution, the present application clamps the edge of the pipe to be bent by the notch of the folding die, and then drives the folding die and / or the pipe to rotate around the edge of the pipe to be bent, so that the folding die forms an angle with respect to the pipe, thereby achieving folding. The technical solution of the embodiment of the present application solves the problem that the mold in the pipe folding mechanism in the prior art is easy to break and has a large loss, improves the efficiency of the pipe folding, and enables the pipe to meet the requirements of subsequent welding.

[0059] In this regard, in order to ensure that the notch of the folding die clamps the edge of the pipe mouth to be bent of the pipe fitting, the folding die includes an upper die and a lower die, and the notch is opened at the connection between the upper die and the lower die. The upper die has a first width, and the first width should not be less than the inner diameter of the pipe mouth of the pipe fitting, so that the upper die can be inserted into the pipe mouth of the pipe fitting and press the inner side of the edge of the pipe mouth to be bent. The lower die has a second width, and the second width can be equal to the first width, can be less than the first width, and can also be greater than the first width. Optimally, the second width can be greater than the outer diameter of the pipe fitting, covering the outer side of the edge of the pipe mouth to be bent, and when folding, the angles on both sides of the pipe mouth can be bent at the same time to ensure the folding effect.

[0060] In addition, the rotating mechanism may include a power mechanism, which is used to apply an upward force to the folding mold and / or the pipe fitting, or to lift one end of the folding mold upward, or to lift the end of the pipe fitting that does not need to be bent upward, or to lift one end of the folding mold and the end of the pipe fitting that does not need to be bent upward respectively. Among them, the power mechanism can apply force in a "lifting" manner or in a "lifting" manner, and the force application method does not limit the present application. The power mechanism can be a power device that can move in a straight line, such as a cylinder, an oil cylinder, or an electric cylinder, or it can adopt other paradigms such as a lifting device, a boom, a manipulator, etc., which does not limit the present application.

[0061] In addition, the rotating mechanism may include a rotating table, the rotating table has a rotating axis, the rotating axis is aligned with the pipe mouth to be bent, the hemming mold or the pipe fitting is installed on the rotating table, and when the rotating table is rotated, the hemming mold or the pipe fitting can be driven to rotate around the pipe mouth to be bent. Alternatively, two rotating tables are provided, the rotating axes of the two rotating tables are arranged opposite to each other or are arranged as the same rotating axis, and the hemming mold and the pipe fitting are respectively arranged on the two rotating tables, so that the hemming mold and the pipe fitting can be driven to rotate at the same time.

[0062] In addition, the folding mechanism may also include a pressing mechanism, which is used to press the pipe or the folding mold during folding so that the pipe or the folding mold will not be displaced during folding. Specifically, if the folding mold is rotated, the pressing mechanism is arranged above the pipe to ensure that the pipe will not be displaced. If the pipe is rotated, the pressing device is arranged above the folding mold to ensure that the folding mold will not be displaced. The pressing mechanism can be a power device capable of linear motion such as a cylinder, an oil cylinder or an electric cylinder, and does not limit the present application.

[0063] In addition, the folding mechanism may also include a demoulding mechanism, which is connected to the folding mold. The main function of the demoulding mechanism is to separate the folding mold from the pipe fitting to facilitate the removal of the pipe fitting. This can be achieved by pulling the folding mold out of the pipe fitting or by lifting the folding mold. This does not limit this application. The demoulding mechanism can be a power device capable of linear motion, such as a cylinder, an oil cylinder, or an electric cylinder, which also does not limit this application.

[0064] The present application also discloses a folding machine having a folding mechanism as described above.

[0065] The present application discloses a folding method, which uses the above-mentioned folding machine to perform folding, and specifically includes the following steps:

[0066] Insertion: insert the edge of the pipe to be bent into the groove of the folding mold, and the folding mold clamps the inner wall of the edge of the pipe to be bent.

[0067] Folding, driving the hemming mold and / or the pipe to rotate around the edge of the pipe to be bent, so that the hemming mold forms an angle with respect to the pipe, and the angle is less than 180°. Specifically, the hemming can be achieved by driving the end of the pipe that does not need to be bent upward to lift up, or by driving one end of the hemming mold and the end of the pipe that does not need to be bent upward to achieve hemming, or by driving one end of the hemming mold and the end of the pipe that does not need to be bent upward to achieve hemming.

[0068] After the folding is completed, the folding mold is pulled out of the pipe fitting, or the folding mold is pushed up to separate the folding mold from the pipe fitting, making it easier to take out the pipe fitting.

[0069] The present application example also discloses a pipe fitting having a folded edge, which is formed by bending the folded edge by the folding mechanism as described above or by bending the folded edge by the folding method as described above.

[0070] The embodiment of the present application also discloses an object having a pipe as described above.

[0071] In the present application, the pipe fittings may be any metal pipe, or may be made of other ductile materials, and the material of the pipe fittings does not limit the technical solution of the present application.

[0072] The pipe fitting may also be a triangular pipe, a rectangular pipe, a polygonal pipe, or even a special-shaped pipe. The shape of the pipe fitting does not limit the technical solution of the present application as long as the edge of the pipe opening to be bent is a straight edge.

[0073] The technical solution of the present application is further illustrated below by using Examples 1-2, but the present application is not limited to these Examples 1-2.

[0074] [Example 1]

[0075] like Figure 1-3 As shown, this embodiment discloses a hemming mechanism, including a hemming die 1 and a rotating mechanism, wherein the hemming die 1 is arranged on the rotating mechanism, and the rotating mechanism drives the hemming die 1 to rotate. One end of the hemming die 1 has a notch 11, into which the edge of the pipe mouth to be bent of the pipe fitting 2 is inserted, and the rotating mechanism drives the hemming die to rotate around the edge of the pipe mouth to be bent, so that the hemming die forms an angle with respect to the pipe fitting, and the angle is less than 180°, so as to realize hemming.

[0076] Specifically, in order to ensure that the notch of the folding die clamps the edge of the pipe mouth to be bent of the pipe fitting, the folding die 1 has an upper die 12 and a lower die 13, and the notch 11 is set at the connection between the upper die 12 and the lower die 13. The upper die 12 has a first width, which is not greater than the inner diameter of the pipe mouth of the pipe fitting 2, so that the upper die 12 can be inserted into the pipe mouth of the pipe fitting 2 and press the inner side of the edge of the pipe mouth to be bent. The lower die 13 has a second width, which is greater than the outer diameter of the pipe fitting 2, covering the outer side of the edge of the pipe mouth to be bent. When folding, the right angles on both sides of the pipe mouth can be bent at the same time to ensure the folding effect.

[0077] Specifically, the rotating mechanism includes a rotating table 3 and a power mechanism 4. The rotating table 3 has a rotating shaft 31, which is aligned with the edge of the pipe mouth to be bent. The hemming mold 1 is installed on the rotating table 3. When the rotating table 3 is rotated, the hemming mold 1 can be driven to rotate around the edge of the pipe mouth to be bent. The power mechanism 4 is arranged on the lower side of the outer end of the rotating table 3, and can be implemented as a power device capable of linear motion such as a cylinder, an oil cylinder or an electric cylinder, which can lift the outer end of the rotating table 3 upward, thereby driving the ungrooved end of the hemming mold 1 to be lifted upward to achieve hemming.

[0078] In addition, the folding mechanism also includes a pressing device 5, which is mounted above the pipe 2 and is used to press the pipe during folding so that the pipe will not move during folding. The pressing mechanism can be a power device capable of linear motion, such as a cylinder, an oil cylinder or an electric cylinder.

[0079] In addition, the hemming mechanism also includes a demoulding mechanism 6, which is also arranged on the rotating table 4 and connected to the hemming mold 1. The hemming mold 1 is inserted into the pipe 2 before hemming, and the hemming mold 1 is pulled out of the pipe 2 after hemming is completed, so that the hemming mold 1 is separated from the pipe 2, which facilitates the removal of the pipe 2. The demoulding mechanism 6 can be a power device capable of linear motion, such as a cylinder, an oil cylinder or an electric cylinder.

[0080] [Example 2]

[0081] like Figure 4-6 As shown, this embodiment discloses a hemming mechanism, including a hemming die 1 and a rotating mechanism, wherein the hemming die 1 is arranged on the rotating mechanism, and the rotating mechanism drives the hemming die 1 to rotate. One end of the hemming die 1 has a notch 11, into which the edge of the pipe mouth to be bent of the pipe fitting 2 is inserted, and the rotating mechanism drives the hemming die to rotate around the edge of the pipe mouth to be bent, so that the hemming die forms an angle with respect to the pipe fitting, and the angle is less than 180°, so as to realize hemming.

[0082] Specifically, in order to ensure that the notch of the hemming die clamps the edge of the pipe mouth to be bent of the pipe fitting, the hemming die 1 has an upper die 12 and a lower die 13. In this embodiment, the upper die 12 is detachable and has multiple upper dies 12, and the multiple upper dies 12 are arranged on the lower die 13. The surface of the lower die 13 has a boss, so that a notch 13 is formed between the front end of the upper die 12 and the lower die 13. The upper die 12 has a first width, and the first width is not less than the inner diameter of the pipe mouth of the pipe fitting, so that the upper die 12 can be inserted into the pipe mouth of the pipe fitting 2 and press the inner side of the edge of the pipe mouth to be bent.

[0083] Specifically, the rotating mechanism includes a rotating table 3 and a power mechanism 4. The rotating table 3 has a rotating shaft 31, which is aligned with the edge of the pipe mouth to be bent. The folding mold 1 is installed on the rotating table 3. When the rotating table 3 is rotated, the folding mold 1 can be driven to rotate around the edge of the pipe mouth to be bent. The power mechanism 4 is arranged on the inner side of the bottom of the rotating table 3, and the body can be implemented as a power device capable of linear motion such as a cylinder, an oil cylinder or an electric cylinder, which can push the bottom of the rotating table 3 outward, and drive the ungrooved end of the folding mold 1 to lift upward to achieve folding.

[0084] In addition, the folding mechanism described in this embodiment also includes a pressing device 5, which is mounted above the pipe 2 and is used to press the pipe during folding so that the pipe will not move during folding. The pressing mechanism can be a power device capable of linear motion, such as a cylinder, an oil cylinder or an electric cylinder.

[0085] In addition, the folding mechanism described in this embodiment also includes a demoulding mechanism 6, which is arranged on the side of the rotating table 4. In this embodiment, the demoulding mechanism 6 is fixedly connected to the upper mold 12 of the folding mold 1, and can push the upper mold 12 upward to separate the upper mold 12 from the lower mold 13 to achieve demoulding. At the same time, it is also convenient to change the size of the upper mold 12 and apply more specifications of pipes. The demoulding mechanism 6 can be a power device capable of linear motion such as a cylinder, an oil cylinder or an electric cylinder.

[0086] Although the above describes the illustrative specific implementation methods of the present application so that technicians in this technical field can understand the present application, the present application is not limited to the scope of the specific implementation methods. For ordinary technicians in this technical field, as long as various changes are within the spirit and scope of the present application defined and determined by the attached claims, all application creations using the concept of the present application are protected.

Claims

1. A folding mechanism, characterized in that: The folding mechanism is used to bend the edge of the pipe mouth to be bent of the pipe fitting, and the edge of the pipe mouth to be bent is a straight edge, and includes: A folding die, one end of which has a notch, and the edge of the tube to be bent is inserted into the notch; A rotating mechanism, wherein the rotating mechanism drives the folding die and / or the pipe to rotate around the edge of the pipe opening to be bent, so that the folding die forms an angle with respect to the pipe, and the angle is less than 180°; The folding die comprises an upper die and a lower die, the lower die is connected to the upper die, and the notch is arranged at the connection between the lower die and the upper die; The upper mold has a first width, and the first width is not greater than the inner diameter of the pipe opening of the pipe fitting; The lower die has a second width, which is greater than the outer diameter of the tube and covers the outer side of the tube opening to be bent; The rotating mechanism includes a power mechanism; The folding mechanism also includes a demoulding mechanism, and the demoulding mechanism is connected to the folding mold; The rotating mechanism comprises a rotating platform, the rotating platform has a rotating axis, and the rotating axis is aligned with the pipe opening to be bent; The power mechanism drives one end of the folding die and the end of the pipe that does not need to be bent to lift up respectively; there are two rotating tables, and the folding die and the pipe are installed on the two rotating tables respectively; Or the power mechanism drives one end of the folding mold to lift upward; the folding mold is installed on the rotating table; Or the power mechanism drives the end of the pipe that does not need to be bent to lift upward; the pipe is installed on the rotating table.

2. A folding mechanism according to claim 1, wherein: The upper mold has a first width, the lower mold has a second width, and the first width is equal to the second width.

3. A folding mechanism according to claim 1, wherein: The upper mold has a first width, the lower mold has a second width, and the first width is greater than the second width.

4. A folding mechanism according to claim 1, wherein: The upper mold has a first width, and the lower mold has a second width, and the first width is smaller than the second width.

5. A folding mechanism according to claim 1, wherein: The folding mechanism also includes a pressing mechanism.

6. A folding mechanism according to claim 5, wherein: The pressing mechanism is arranged above the pipe.

7. A folding mechanism according to claim 5, wherein: The pressing mechanism is arranged above the folding mould.

8. A folding machine, characterized in that: A folding mechanism as claimed in any one of claims 1 to 7.

9. A folding method, characterized in that: The folding method is based on a folding mechanism according to any one of claims 1 to 7, The following steps are involved: Insertion: insert the edge of the pipe to be bent into the groove of the folding die; Folding drives the folding mold and / or the pipe fitting to rotate around the edge of the pipe mouth to be bent, so that the folding mold forms an angle with respect to the pipe fitting, and the angle is less than 180°.

10. A hemming method as claimed in claim 9, wherein: In the inserting step, the folding die clamps the inner wall of the edge of the pipe mouth to be bent.

11. A hemming method as claimed in claim 9, wherein: In the folding step, one end of the folding mold is driven to lift upward to achieve folding.

12. A hemming method as claimed in claim 9, wherein: In the folding step, the end of the pipe that does not need to be bent is driven to lift up to achieve folding.

13. A hemming method as claimed in claim 9, wherein: In the folding step, one end of the folding mold and the end of the tube that does not need to be bent are lifted upward to achieve folding.

14. A hemming method as claimed in claim 9, wherein: Before the hemming step, the hemming mold or the tube is pressed tightly.

15. A hemming method as claimed in claim 9, wherein: After the hemming step, the hemming die is pulled out of the tube.

16. A hemming method as claimed in claim 9, wherein: After the hemming step, the tube is separated from the hemming mold by lifting the hemming mold upward.

17. A pipe fitting, characterized in that: The pipe fitting has a folded edge, which is a straight edge. The folded edge is formed by bending by the folding mechanism described in any one of claims 1 to 7 or by bending by the folding method described in any one of claims 9 to 16.

18. A pipe fitting according to claim 17, wherein: The pipe fitting is a triangular pipe, a rectangular pipe, a polygonal pipe, a semicircular pipe or a special-shaped pipe.

19. An object, characterized in that A pipe fitting according to any one of claims 17-18.

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